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Dive into the research topics where Gayan Perera is active.

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Featured researches published by Gayan Perera.


PLOS ONE | 2011

Life Expectancy at Birth for People with Serious Mental Illness and Other Major Disorders from a Secondary Mental Health Care Case Register in London

Chin-Kuo Chang; Richard D. Hayes; Gayan Perera; Mathew T. M. Broadbent; Andrea Fernandes; William Lee; Matthew Hotopf; Robert Stewart

Objective Despite improving healthcare, the gap in mortality between people with serious mental illness (SMI) and general population persists, especially for younger age groups. The electronic database from a large and comprehensive secondary mental healthcare provider in London was utilized to assess the impact of SMI diagnoses on life expectancy at birth. Method People who were diagnosed with SMI (schizophrenia, schizoaffective disorder, bipolar disorder), substance use disorder, and depressive episode/disorder before the end of 2009 and under active review by the South London and Maudsley NHS Foundation Trust (SLAM) in southeast London during 2007–09 comprised the sample, retrieved by the SLAM Case Register Interactive Search (CRIS) system. We estimated life expectancy at birth for people with SMI and each diagnosis, from national mortality returns between 2007–09, using a life table method. Results A total of 31,719 eligible people, aged 15 years or older, with SMI were analyzed. Among them, 1,370 died during 2007–09. Compared to national figures, all disorders were associated with substantially lower life expectancy: 8.0 to 14.6 life years lost for men and 9.8 to 17.5 life years lost for women. Highest reductions were found for men with schizophrenia (14.6 years lost) and women with schizoaffective disorders (17.5 years lost). Conclusion The impact of serious mental illness on life expectancy is marked and generally higher than similarly calculated impacts of well-recognised adverse exposures such as smoking, diabetes and obesity. Strategies to identify and prevent causes of premature death are urgently required.


BMJ Open | 2016

Cohort profile of the South London and Maudsley NHS Foundation Trust Biomedical Research Centre (SLaM BRC) Case Register : current status and recent enhancement of an Electronic Mental Health Record-derived data resource.

Gayan Perera; Matthew Broadbent; Felicity Callard; Chin-Kuo Chang; Johnny Downs; Rina Dutta; Andrea Fernandes; Richard D. Hayes; Max Henderson; Richard Jackson; Amelia Jewell; Giouliana Kadra; Ryan Little; Megan Pritchard; Hitesh Shetty; Alexander Tulloch; Robert Stewart

Purpose The South London and Maudsley National Health Service (NHS) Foundation Trust Biomedical Research Centre (SLaM BRC) Case Register and its Clinical Record Interactive Search (CRIS) application were developed in 2008, generating a research repository of real-time, anonymised, structured and open-text data derived from the electronic health record system used by SLaM, a large mental healthcare provider in southeast London. In this paper, we update this registers descriptive data, and describe the substantial expansion and extension of the data resource since its original development. Participants Descriptive data were generated from the SLaM BRC Case Register on 31 December 2014. Currently, there are over 250 000 patient records accessed through CRIS. Findings to date Since 2008, the most significant developments in the SLaM BRC Case Register have been the introduction of natural language processing to extract structured data from open-text fields, linkages to external sources of data, and the addition of a parallel relational database (Structured Query Language) output. Natural language processing applications to date have brought in new and hitherto inaccessible data on cognitive function, education, social care receipt, smoking, diagnostic statements and pharmacotherapy. In addition, through external data linkages, large volumes of supplementary information have been accessed on mortality, hospital attendances and cancer registrations. Future plans Coupled with robust data security and governance structures, electronic health records provide potentially transformative information on mental disorders and outcomes in routine clinical care. The SLaM BRC Case Register continues to grow as a database, with approximately 20 000 new cases added each year, in addition to extension of follow-up for existing cases. Data linkages and natural language processing present important opportunities to enhance this type of research resource further, achieving both volume and depth of data. However, research projects still need to be carefully tailored, so that they take into account the nature and quality of the source information.


British Journal of Psychiatry | 2009

The psychiatric case register: noble past, challenging present, but exciting future

Gayan Perera; Mishael Soremekun; Gerome Breen; Robert Stewart

Case registers have been fundamental to mental health research from the early asylum studies onwards. Having declined in popularity over the past 20 years, they are likely to see a resurgence of interest with the advent of electronic clinical records and the technological capacity to derive anonymised databases from these.


PLOS ONE | 2014

Factors Associated with Response to Acetylcholinesterase Inhibition in Dementia: A Cohort Study from a Secondary Mental Health Care Case Register in London

Gayan Perera; Mizanur Khondoker; Matthew Broadbent; Gerome Breen; Robert Stewart

Background Acetylcholinesterase inhibitors (AChEIs) are widely used to delay cognitive decline in Alzheimers disease. Observational studies in routine clinical practice have shown cognitive improvement in some groups of patients receiving these agents but longitudinal trajectories before and after AChEI initiation have not previously been considered. Objectives To compare trajectories of cognitive function before and after AChEI initiation and investigate predictors of these differences. Method A retrospective longitudinal study was constructed using data from 2460 patients who received AChEIs and who had routine data on cognitive function (Mini-Mental State Examination; MMSE) before and after AChEI initiation. Longitudinal MMSE change was modelled using three-piece linear mixed models with the following segments: 0–12 months prior to AChEI initiation, 0–6 months and 6–36 months after initiation. Results MMSE decline was reversed (in that the slope was improved by an average 4.2 units per year, 95% CI 3.5–4.8) during the 6-month period following AChEI initiation compared with the slope in the one year period before AChEI initiation. The slope in the period from 6–36 months following AChEI initiation returned to the pre-initiation downward trajectory. The differences in slopes in the 1 year period prior to AChEI initiation and in the 6 months after initiation were smaller among those with higher MMSE scores at the time of AChEI initiation, among those who received a vascular dementia diagnosis at any point, and among those receiving antipsychotic agents. Conclusion In this naturalistic observational study, changes in cognitive trajectories around AChEI initiation were similar to those reported in randomised controlled trials. The magnitude of the difference in slopes between the 1 year period prior to AChEI initiation and the 6 month period after AChEI initiation was related to level of cognitive function at treatment initiation, vascular comorbidity and antipsychotic use.


Age and Ageing | 2016

Reporting of clinically diagnosed dementia on death certificates: retrospective cohort study

Gayan Perera; Robert Stewart; Irene J. Higginson; Katherine E Sleeman

Background: mortality statistics are a frequently used source of information on deaths in dementia but are limited by concerns over accuracy. Objective: to investigate the frequency with which clinically diagnosed dementia is recorded on death certificates, including predictive factors. Methods: a retrospective cohort study assembled using a large mental healthcare database in South London, linked to Office for National Statistics mortality data. People with a clinical diagnosis of dementia, aged 65 or older, who died between 2006 and 2013 were included. The main outcome was death certificate recording of dementia. Results: in total, 7,115 people were identified. Dementia was recorded on 3,815 (53.6%) death certificates. Frequency of dementia recording increased from 39.9% (2006) to 63.0% (2013) (odds ratio (OR) per year increment 1.11, 95% CI 1.07–1.15). Recording of dementia was more likely if people were older (OR per year increment 1.02, 95% CI 1.01–1.03), and for those who died in care homes (OR 1.89, 95% CI 1.50–2.40) or hospitals (OR 1.14, 95% CI 1.03–1.46) compared with home, and less likely for people with less severe cognitive impairment (OR 0.95, 95% CI 0.94–0.96), and if the diagnosis was Lewy body (OR 0.30, 95% CI 0.15–0.62) or vascular dementia (OR 0.79, 95% CI 0.68–0.93) compared with Alzheimers disease. Conclusions: changes in certification practices may have contributed to the rise in recorded prevalence of dementia from mortality data. However, mortality data still considerably underestimate the population burden of dementia. Potential biases affecting recording of dementia need to be taken into account when interpreting mortality data.


Journal of Alzheimer's Disease | 2015

Age-Stratified Prevalence of Mild Cognitive Impairment and Dementia in European Populations: A Systematic Review

Myriam Alexander; Gayan Perera; Lisa Ford; H. Michael Arrighi; Nadia Foskett; Catherine Debove; Gerald Novak; Mark Forrest Gordon

The prevalence of mild cognitive impairment (MCI) and dementia according to age remain uncertain. We systematically extracted age-stratified estimates of MCI and dementia prevalence reported in European studies published since 1995, and performed meta-analyses for dementia. We identified 10 relevant studies on MCI and 26 studies on dementia. Studies on MCI presented substantial heterogeneity preventing a meta-analysis, with a majority reporting an increase in prevalence at ≥75 years old. Pooled prevalence of dementia rose continuously from 55 years of age, reaching 44.7% (39.8; 49.6) in those ≥95 years of age. Homogenization of MCI criteria, and additional studies in Northern European population would be warranted.


PLOS ONE | 2014

Mini-Mental State Examination as a Predictor of Mortality among Older People Referred to Secondary Mental Healthcare

Yu-Ping Su; Chin-Kuo Chang; Richard D. Hayes; Gayan Perera; Matthew Broadbent; David To; Matthew Hotopf; Robert Stewart

Background Lower levels of cognitive function have been found to be associated with higher mortality in older people, particularly in dementia, but the association in people with other mental disorders is still inconclusive. Methods and Findings Data were analysed from a large mental health case register serving a geographic catchment of 1.23 million residents, and associations were investigated between cognitive function measured by the Mini-Mental State Examination (MMSE) and survival in patients aged 65 years old and over. Cox regressions were carried out, adjusting for age, gender, psychiatric diagnosis, ethnicity, marital status, and area-level socioeconomic index. A total of 6,704 subjects were involved, including 3,368 of them having a dementia diagnosis and 3,336 of them with depression or other diagnoses. Descriptive outcomes by Kaplan-Meier curves showed significant differences between those with normal and impaired cognitive function (MMSE score<25), regardless of a dementia diagnosis. As a whole, the group with lower cognitive function had an adjusted hazard ratio (HR) of 1.42 (95% CI: 1.28, 1.58) regardless of diagnosis. An HR of 1.23 (95% CI: 1.18, 1.28) per quintile increment of MMSE was also estimated after confounding control. A linear trend of MMSE in quintiles was observed for the subgroups of dementia and other non-dementia diagnoses (both p-values<0.001). However, a threshold effect of MMSE score under 20 was found for the specific diagnosis subgroups of depression. Conclusion Current study identified an association between cognitive impairment and increased mortality in older people using secondary mental health services regardless of a dementia diagnosis. Causal pathways between this exposure and outcome (for example, suboptimal healthcare) need further investigation.


International Journal of Geriatric Psychiatry | 2015

Predictors of mortality for people aged over 65 years receiving mental health care for delirium in a South London Mental Health Trust, UK: a retrospective survival analysis

Geoff Ward; Gayan Perera; Robert Stewart

Delirium is a common phenomenon in older people. Using a large mental health care data resource, we investigated mortality rates and predictors of mortality following delirium in older people.


Age and Ageing | 2018

Associations of acetylcholinesterase inhibitor treatment with reduced mortality in Alzheimer's disease: a retrospective survival analysis

Christoph Mueller; Gayan Perera; Richard D. Hayes; Hitesh Shetty; Robert Stewart

Background dementia is increasingly recognised as life-limiting condition. Although the benefits of acetylcholinesterase inhibitors (AChEIs) on cognition and function are well established, their effect on survival is less clear. Objective to investigate associations between AChEI prescription and mortality in patients with Alzheimers dementia (AD) in a naturalistic setting, using detailed baseline data on cognition, functioning, and mental and physical wellbeing. Methods we used a large mental healthcare database in South London, linked to Hospital Episode Statistics and Office for National Statistics mortality data, to assemble a retrospective cohort. We conducted a survival analysis adjusting for a wide range of potential confounders using propensity scores to reduce the impact of confounding by indication. Results of 2,464 patients with AD, 1,261 were prescribed AChEIs. We detected a strong association between AChEI receipt and lower mortality (hazard ratio = 0.57; 95% CI 0.51-0.64). This remained significant after controlling for a broad range of potential confounders including psychotropic co-prescription, symptom severity, functional status and hospital admissions (hazard ratio = 0.77; 95% CI 0.67-0.87). Conclusions in a large cohort of patients with AD, AChEI prescription was associated with reduced risk of death by more than 20% in adjusted models. This has implications for individual care planning and service development.


Experimental Gerontology | 2018

Polypharmacy in people with dementia: Associations with adverse health outcomes

Christoph Mueller; Mariam Molokhia; Gayan Perera; Nicola Veronese; Brendon Stubbs; Hitesh Shetty; David Codling; Jonathan Huntley; Robert Stewart

&NA; Polypharmacy has been linked to higher risks of hospitalisation and death in community samples. It is commonly present in people with dementia but these risks have rarely been studied in this population. We aimed to investigate associations between polypharmacy and emergency department attendance, any and unplanned hospitalisation, and mortality in patients with dementia. Using a large mental health care database in South London, linked to hospitalisation and mortality data, we assembled a retrospective cohort of patients diagnosed with dementia. We ascertained number of medications prescribed at the time of dementia diagnosis and conducted multivariate Cox regression analyses. Of 4668 patients with dementia identified, 1128 (24.2%) were prescribed 4–6 medications and 739 (15.8%) ≥7 medications. Compared to those using 0–3 medications, patients with dementia using 4–6 or ≥7 agents had an increased risk of emergency department attendance (hazard ratio 1.20/1.35), hospitalisation (hazard ratio 1.12/1.32), unplanned hospital admission (hazard ratio 1.12/1.25), and death within two years (hazard ratio 1.29/1.39) after controlling for potential confounders. We found evidence of a dose response relationship with each additional drug at baseline increasing the risk of emergency department attendance and mortality by 5% and hospitalisation by 3%. In conclusion, polypharmacy at dementia diagnosis is associated with a higher risk of adverse health outcomes. Future research is required to elucidate which specific agents underlie this relationship and if reduction of inappropriate prescribing is effective in preventing these outcomes in dementia.

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Matthew Broadbent

South London and Maudsley NHS Foundation Trust

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Brendon Stubbs

South London and Maudsley NHS Foundation Trust

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